As May comes to a close, we're a little less than 100 days until regular-season football returns, and for now let's forget the whole notion of NFL power rankings and how teams stack up. How about the pressure rankings instead, with our list featuring the quarterbacks who for a variety of reasons will play under the microscope of high expectations even more than usual in 2018?

Manning the NFL's most pressurized position puts quarterbacks perpetually on the spot, but this is a year that feels like it has a larger than normal contingent of passers feeling the heat as the season looms. For these 15 quarterbacks, the need to perform at or near their best in 2018 is palpable. Here's my assessment of who'll be under the gun, needing to produce, when the season kicks off in September:

1. Joe Flacco, Baltimore

Say it ain't so, Joe. But alas the spotlight falls first and foremost on Flacco for good reason. Name me another 10-year starter/incumbent who's playing for his future this season, with his team having drafted his potential replacement in the first round and the reality of no longer owing him any guaranteed money after 2018. Even Eli Manning has more job security than that at the moment.

Then again, the last time Flacco faced this much pressure, his bet-on-himself gambit worked exquisitely five years ago, with Baltimore storming to the Super Bowl win that made him a very well-rewarded franchise cornerstone. But the Ravens have missed the playoffs in four of the past five seasons, and Flacco is now 33, with an iffy back and a middling showing of late. Whether Lamar Jackson is the answer for Baltimore's future or not, the questions about Flacco have reached the make-or-break juncture.

2. Patrick Mahomes, Kansas City

Having made the playoffs in four of the five seasons veteran Alex Smith was their starter — never winning more than one playoff game in any year — the Chiefs gambled that Mahomes' upside is much higher and traded away Smith to Washington during Super Bowl week. Now it's on Mahomes to prove Kansas City was wise to trust in him, despite him having started just one game in a meaningless Week 17 situation as a rookie. If Smith stars in D.C. while Mahomes endures growing pains, with Kansas City losing ground after winning consecutive AFC West titles for the first time in franchise history, it's going to be one of the most second-guessed moves in recent NFL history.

3. Ryan Tannehill, Miami

The Dolphins are still waiting on the big payoff after investing a top-10 pick on Tannehill in 2012, and after missing all of last season due to an ACL injury, even he acknowledges it's now-or-never for him in Miami in 2018. If he's the same guy who had the Dolphins on track for the playoffs in 2016 before being hurt in December — he logged a career-best 93.5 passer rating that season — he'll likely continue to be coach Adam Gase's guy moving forward. But if his penchant for inconsistency returns, don't be surprised if Miami turns to Brock Osweiler or even Bryce Petty at some point this year and then goes hunting for a new starter in 2019.

4. Derek Carr, Oakland

His stellar 2016 performance inspired MVP buzz and put him on a trajectory to be thought of as one of the game's next greats, but last season was the ultimate buzz kill for the Raiders' fourth-year passer. Carr wasn't awful by any stretch, but he definitely regressed toward mediocrity and now it's coach Jon Gruden's job to help resurrect his game and return him to the ranks of the ascendant.

Gruden's rep as a quarterback whisperer is mostly TV-created hype, because he has rarely been satisfied with the passer he has, instead coveting the next available arm to hit the market. That reality creates early pressure on the Carr-Gruden relationship, and while both of them are singing one another's praises in late May, let's see how the coach's notorious tough-love approach wears on his still-young quarterback once the games start counting this fall.

5. Jameis Winston, Tampa Bay

By all accounts, the Bucs have had a very hopeful offseason on the talent acquisition front and look ready to rebound from last year's dismal 5-11, last-place finish in the rugged NFC South. But it's curious that one of their objectives this spring has been to try and ease Winston's self-created pressure, getting him to lighten up on himself and not fail the stress test. Newly elevated offensive coordinator Todd Monken even went so far this month as to tell Winston: "You don't have to try so hard. Guys will follow you. Just be yourself.'' 

Winston does indeed want it badly, but through his first three NFL seasons, success has been fleeting. The Bucs are still their own worst enemy at times and you have only to think back to how they gave away that Week 5 Thursday night home game against New England last season as a prime example. With coach Dirk Koetter again on the hot seat this year, and Winston still having not reached the playoffs in the first three seasons of his career, it's win-now time in Tampa Bay.

6. Andrew Luck, Indianapolis

The pressure of the unknown remains one of the most fearsome pressures of all, and that's unfortunately what Luck faces as he attempts to finally get past the shoulder injury/surgery/setbacks that robbed him of the entire 2017 season. He's capable of carrying this Colts team, as he did in 2012-2014, when Indianapolis won 11 games and made the playoffs each season. But the hope is the Colts have built a better roster around him under second-year general manager Chris Ballard and new head coach Frank Reich, and that Luck's natural ability and leadership has survived intact, making Indianapolis relevant once more in the vastly-improved AFC South.

7. Kirk Cousins, Minnesota

To whom much is given, much will be required, and that's the biblical slant on Cousins' historic fully-guaranteed $84-million three-year free-agent contract, which has done nothing but crank up the Super Bowl-or-bust vibe in Minnesota. I happen to think he'll be up to the task of meeting expectations and will thrive on this, the best team he's ever played for. But the measuring stick will be crystal clear. The Vikings need to go further than the NFC title game this season, and Cousins needs to out-do anything accomplished in 2018 by the three former Vikings starters in their new locations: Case Keenum in Denver, Sam Bradford in Arizona and Teddy Bridgewater with the Jets.

8. Case Keenum, Denver

The Broncos say they trusted their eyes and liked Keenum's work in Minnesota last season even more than they did Kirk Cousins' in Washington, dictating their first choice in free agency. Fair enough. Keenum's break-through season with the Vikings was the picture of steadiness and winning quarterbacking, and they may well have placed their bet on the right guy. But let's see what the resilient Keenum has for a follow-up act and if he can reverse the fortunes of Broncos team that fell all the way to 5-11 and last place just two years removed from a Super Bowl title. This time around he won't be cast in the role of over-achieving backup turned surprise starter, he'll be the focal point in a football-mad market that is not used to losing.

9. Eli Manning, New York Giants

Okay, Eli, show us what you've (still) got. With a new coach (Pat Shurmur) and general manager (Dave Gettleman) who believes in his 37-year-old self, plus upgraded weapons and an improved offensive line, it's up to Manning to prove the Giants were correct to bypass drafting a franchise quarterback at No. 2 overall. If his game falters, it won't be Ben McAdoo's fault this time.

10. Andy Dalton, Cincinnati

Granted, there's no outward sign that anyone in the Bengals organization works with much of a threat to their job security. But at some point, the long leash that both coach Marvin Lewis and Dalton have received in Cincinnati has to tighten and snap, and that makes them a perennial under pressure tandem. Now that the Bengals for two years running can't even fall back on the handy at-least-we-made-the-playoffs diversion, time has to be running out on Dalton's up-and-down tenure if a significant upswing is not in the offing in 2018. With the Bengals having a full season of offensive coordinator Bill Lazor, and former Cincinnati backup quarterback A.J. McCarron now in position to start for Buffalo, the onus is on Dalton to change what has become a tired narrative of offensive underachievement in the Queen City.

11. Blake Bortles, Jacksonville

Jacksonville showed its confidence in Bortles with a three-year contract extension this offseason, but it wasn't at the level of commitment that puts him on easy street with nothing to worry about in terms of long-term job security. He needs to prove he can stay consistent and be the difference-maker he was in the postseason, without lapsing back into the sloppy ball-protection he was known for prior to 2017. The Jaguars are a team with legitimate Super Bowl dreams, and Bortles can't be the one who holds them back.

12. Jimmy Garoppolo, San Francisco

It has been a Jimmy G. love-fest so far in 49ers-land, with a win-starved franchise fawning over him and lavishing him with a pace-setting contract that rewards him far in excess of his small-sample-size 5-0 record as the San Francisco starter. Kyle Shanahan's team is a chic pick as an NFC playoff contender, but so much of that projection is built on the hope that Garoppolo is as poised for greatness as he looked late last season. It's time for him to turn promise and potential into week-in and week-out production over the course of a full season.

13. Dak Prescott, Dallas

Great as a rookie in 2016, Prescott was merely decent to very good last season, showing signs of regression on the interception front (four in 2016 and 13 in 2017). If he's going to earn the big-money extension he seeks by 2019, he's going to have to show he's the centerpiece of the Cowboys offense and a player who elevates those around him. There's always pressure when you're playing for a big contract.

14. Carson Wentz, Philadelphia

Wentz's future is undeniably bright in Philadelphia, but the reality is he's coming back from a major knee injury after watching his backup, Nick Foles, earn Super Bowl MVP honors for the newly christened champs. That's not the most pressure-free scenario to face in 2018, especially since his early-season availability remains unknown.

15. Alex Smith, Washington

Smith's inclusion means the NFC East features all four teams with starting quarterbacks facing varying levels of pressure. Smith has quarterbacked a playoff-qualifying team in six of his past seven seasons, so his track record is a winning one from 2011-on. But if he struggles in his transition to Washington, it's going to create questions about coach Jay Gruden's job status, and dredge up the franchise's dubious handling of Kirk Cousins' contract situation. If that high-impact decision gets re-visited almost immediately in D.C., it's not a good development for anyone.